Eyeworld

89 EW INTERNATIONAL August 2017 by Stefanie Petrou Binder, MD, EyeWorld Contributing Writer New study accounts for the large variability in antibiotic prophylaxis of postop endophthalmitis in cataract surgery in England G uidelines set by the Royal College of Ophthalmol- ogists for the prophy- laxis against infection after cataract surgery are relatively simple. 1 In addition to the use of preoperative povidone iodine 5% aqueous solution irrigated into the conjunctival sac, the Royal College advises the application of intracameral cefuroxime if local, regional rates of endophthalmitis exceed 0.55% per 1,000 cataract extractions. 2 If local rates of endoph- thalmitis are below this benchmark, surgeons can continue with their current regimen. This policy allows for a fair amount of flexibility in the English surgeons' approach to endophthalmitis prophylaxis. Common practice in England "Elective phacoemulsification with intraocular lens replacement is the most commonly performed oper- ation in the NHS, with a rare but devastating complication of post- operative endophthalmitis," said Munazzah Chou, MD, East Surrey Hospital, Redhill, United Kingdom, during a presentation at the 21st Winter Meeting of the European Society of Cataract & Refractive Surgeons (ESCRS). "Current Europe- an guidelines recommend intraca- meral cefuroxime for prophylaxis in cataract surgery, however, the Royal College of Ophthalmologists allows local departments a choice in drug and the route of administration, in areas where endophthalmitis rates are low." Dr. Chou's study surveyed ophthalmologists within the East of England to assess the choice and route of antibiotics implemented in cataract surgery within the region. The survey questions addressed surgeons' routine antibiotic choice in cataract surgery, the agents being prescribed for patients with allergies particularly to penicillin, and infor- mation regarding local guidelines on post-cataract prophylaxis mea- sures. Responses were received from 27 regional surgeons, 11 of them independent and 16 in training at either teaching (32%) or district general hospitals (68%). According to the study's out- comes, 21 of the 27 surgeons rou- tinely gave intracameral cefuroxime in cataract surgery, five gave intraca- meral vancomycin, and one surgeon reported giving only topical chlor- amphenicol. Three surgeons used intracameral cefuroxime for their pa- tients with a penicillin allergy based on a history of anaphylaxis, and 24 replaced cefuroxime with intracam- eral vancomycin, subconjunctival gentamicin, or topical antibiotics. Twenty-three respondents worked in a department without a policy for endophthalmitis prophylaxis or were not aware of a policy. Background A report from the ESCRS shows that endophthalmitis rates have dropped appreciably in recent years thanks to the introduction of intracameral injections as a routine method of prophylaxis after cataract surgery. 3 According to the published data from this report, endophthalmitis rates were between 0.3% and 1.2% prior to the institution of intracam- eral cefuroxime, given at the close of cataract surgery, which dropped to 0.014% to 0.08% following the institution of intracameral cefurox- ime. The reduction corresponds to a seven- to 28-fold overall decrease in endophthalmitis incidence. As a result, this practice has been large- ly adopted, with most European centers now utilizing intracameral cefuroxime. According to outcomes from a prospective, randomized, partially masked multicenter cataract surgery study that recruited 16,603 pa- tients who were treated with either intracameral cefuroxime or topical perioperative levofloxacin, 29 pa- tients presented with endophthalmi- tis, of whom 20 were classified with proven infective endophthalmitis. The absence of an intracameral cefuroxime prophylactic regimen at 1 mg in 0.1 ml normal saline was associated with a 4.92-fold increased risk in developing endophthalmitis. The use of clear corneal incisions as opposed to scleral tunnels was associated with a 5.88-fold risk, and silicone compared to acrylic IOL ma- terial with a 3.13-fold increased risk in developing endophthalmitis. 4 Allergy Cataract surgeons often choose to avoid using cephalosporins in penicillin-resistant patients, opting for a safer course of endophthalmitis prophylaxis with the use of different agents, and thus avoiding possible cross-sensitivity between these drug classes. Newer generation cephalo- sporin antibiotics, however, have a low likelihood of allergic reactions. 5 "In our study, two-thirds of surgeons followed ESCRS guidelines by prescribing intracameral cefu- roxime intraoperatively," Dr. Chou said. "However, only three out of 27 ophthalmologists used intracameral cefuroxime in penicillin-allergic pa- tients. Second- to fourth-generation cephalosporins including cefurox- ime do not share a similar side chain with penicillin and therefore do not share an increased risk of allergic reaction or cross-allergenicity. In Sweden, every patient undergoing cataract surgery receives intracamer- al cefuroxime unless the patient has a distinct allergy to cephalosporins so that the focus of concern is aller- gy to cephalosporins, not allergy to penicillin." In a literature review on the use of cephalosporins in penicillin-aller- gic patients that incorporated Med- line published studies from 1950 to 2012, the overall cross-reactivity rate between penicillin and cephalospo- rins was approximately 1%, when using first-generation cephalosporins or cephalosporins with similar R1 side chains. 6 The review confirmed that the molecules' R1 side chain was responsible for cross-reactivi- ty, and showed a negligible risk of cross-allergy for penicillin-resistant patients given third- or fourth-gen- eration cephalosporins or cephalo- sporins with dissimilar side chains. "Variability exists in the practice of antibiotic prophylaxis of en- dophthalmitis post-cataract surgery in East of England, which is even greater for patients with penicillin allergy. This variability within the region may be replicated throughout the country. This suggests a need for a nationwide study to correlate practice and outcomes," Dr. Chou said. EW References 1. The Royal College of Ophthalmologists. Cataract Surgery Guidelines. Published by the Royal College of Ophthalmologists. September 2010. 2. Kelly SP, et al. Reflective consideration of postoperative endophthalmitis as a quality marker. Eye (Lond). 2007;21:1419–26. 3. Barry P, et al. ESCRS Guidelines for Prevention and Treatment of Endophthalmitis Following Cataract Surgery: Data, Dilemma and Conclusions. Published by the European Society of Cataract & Refractive Surgeons. 2013. 4. Endophthalmitis Study Group, European Society of Cataract & Refractive Surgeons. Prophylaxis of postoperative endophthalmitis following cataract surgery: results of the ESCRS multicenter study and identification of risk factors. J Cataract Refract Surg. 2007;33:978–88. 5. Steber C. Penicillin and cephalosporin cross-reactivity and risk for allergic reaction. Published by Evidence-Based Medicine Con- sult. August 2015. 6. Campagna JD, et al. The use of cephalospo- rins in penicillin-allergic patients: a literature review. J Emerg Med. 2012;42:612–20. Editors' note: Dr. Chou has no financial interests related to his comments. Contact information Chou: mchou@doctors.org.uk English cataract surgeons maintain a free hand Presentation spotlight " The Royal College of Ophthalmologists allows local departments a choice in drug and the route of administration, in areas where endophthalmitis rates are low. " —Munazzah Chou, MD

• Blank Page
• Blank Page (1)